Evolution And Speciation In Protozoa

Author : T.J. Pandian
Publisher : CRC Press
ISBN 13 : 1000838609
Total Pages : 220 pages
Book Rating : 4.02/5 ( download)

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Download or read book Evolution and Speciation in Protozoa written by T.J. Pandian and published by CRC Press. This book was released on 2023-02-24 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: The polyphyletic Protozoa have explored the possibility of performing almost all metazoan functions with a few subcellular organelles. Their unicellularity and structural simplicity have (i) limited diversity to 32,950 species, (ii) restricted spatial distribution to aquatic habitats (94%, against 15% in Metazoa), (iii) demonstrated the ubiquitous dominance of clonality, (iv) reduced sexualization in 50% species, (v) facilitated the use of vegetative gametes in 40% species and (vi) secondary loss of sex in 10% species. With the fastest multiplication rates, i.e. once every 6-60 hours, they occur in high densities of 105-106 cell/ml. Their diverse and complicated life cycles are described in 30 types. Being risky, the cycle involves two hosts in clonality > hermaphroditism > motility. Motility ranges from 2-3 μm for Rhizopoda to 400-2,000 μm for Ciliophora. Not surprisingly, 6,800 species of arcellinids, filosians and formainifers are testated or shelled. Within 1,229 sessile species, the peritrichid and suctorian ciliates are better adapted to coloniality. Unlike those of many Metazoa, the protozoan cyst is a dynamic stage, in which clonal or sexual reproduction occurs. Over 81% protozoans encyst, as it ensures (i) 90% survival during unfavorable conditions (against 15 in 12% non-encysted protozoans), (ii) genome transfer through generations, (iii) dispersal into new habitats and (iv) transmission to new hosts. Their mean body size ranges from 2 μm to 2 mm – a range over 1,000-times – only 8% aquatic metazoans cover a similar size range. In comparison to 77% macrophagy in Metazoa, only 46% protozoans are macrophagous predators. Within motile microphagy, protozoans filter 3-2 times smaller food particle at 50% cheaper clearance cost. This efficiency has expanded microphagy to 15% in protozoans, against 3% in Metazoa. Hence, their turnover rate in trophic dynamics is twice faster than that of metazoans. Foraminifers serve as ecological sensitive indicators in petroleum exploration and rise in sea level. For the first time, incidences of clonality and meiosis as well as symbiosis and parasitism have been shown to hint at the origin and evolution of different protozoan taxonomic groups during the geological past.

Author : Graham H. Coombs
Publisher : Springer
ISBN 13 : 9780412798009
Total Pages : 0 pages
Book Rating : 4.0X/5 ( download)

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Download or read book Evolutionary Relationships Among Protozoa written by Graham H. Coombs and published by Springer. This book was released on 1998-10-31 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The evolutionary biology of protozoa is a field in which exciting changes are taking place. Relationships between different groups of protozoa are undergoing extensive review and the revised views will have significant repercussions for future investigations. New data from molecular and ultrastructural studies have changed our perception of evolution among this diverse group of organisms in recent years. This volume, part of the Systematics Association Special Volume Series, aims to review this important area and give an up-to-date synthesis of current understanding. The various chapters are deliberately broad in scope and explore areas such as the contribution of different techniques and approaches to the understanding of protistan evolution and the biochemical and physiological aspects of that evolution; there are also chapters that analyse and explore specific protistan groups. In addition some of the chapters discuss topics that are currently very controversial within this field, such as the finding that the 18S rRNA phylogenetic tree of protozoa is probably unreliable. The world-renowned editors have assembled an international team of outstanding scientists whose contributions have produced a volume of interest to all evolutionary biologists and especially those interested in protozoa.

Author : Genoveva F. Esteban
Publisher : Springer Nature
ISBN 13 : 3030599795
Total Pages : 188 pages
Book Rating : 4.99/5 ( download)

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Download or read book Ecology of Protozoa written by Genoveva F. Esteban and published by Springer Nature. This book was released on 2021-01-04 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book emphasises the important role that protozoa play in many natural ecosystems. To shed new light on their individual adaptive skills, the respective chapters examine the ecology and functional biology of this diverse group of eukaryotic microbes. Protozoa are well-established model organisms that exemplify many general problems in population ecology and community ecology, as well as evolutionary biology. Their particular characteristics, like large population sizes, life cycles and motile sensory behaviour, have a profound impact on their survival, distribution, and interaction with other species. Thus, readers will also be introduced to protozoan habitats in a broad range of environments. Even though this group of unicellular organisms is highly diverse, the authors focus on shared ecological patterns. Students and scientists working in the areas of eukaryotic microbiology and ecology will appreciate this updated and revised 2nd Edition as a valuable reference guide to the “lifestyles” of protozoa.

Author : Daniel J. Howard
Publisher : Oxford University Press, USA
ISBN 13 : 9780195109016
Total Pages : 486 pages
Book Rating : 4.15/5 ( download)

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Download or read book Endless Forms written by Daniel J. Howard and published by Oxford University Press, USA. This book was released on 1998 with total page 486 pages. Available in PDF, EPUB and Kindle. Book excerpt: Speciation is one of the great themes of evolutionary biology. It is the process through which new species are born and diversity generated. Yet for many years our understanding of the process consisted of little more than a perception that if populations are isolated geographically, they will diverge genetically and may come to form new species. This situation began to change in the 1960s as an increasing number of biologists challenged the exclusivity of allopatric speciation and began to probe more deeply into the actual process by which divergence occurs and reproductive isolation is acquired. This focus on process led to many new insights, but numerous questions remain and speciation is now one of the most dynamic areas of research in modern evolutionary biology. This volume presents the newest research findings on speciation bringing readers up to day on species concepts, modes of speciation, and the nature of reproductive barriers. It also discusses the forces that drive divergence of populations, the genetic control of reproductive isolation, and the role played by hybrid zones and hybridization in speciation.

Author : Dale H. Clayton
Publisher : Oxford University Press, USA
ISBN 13 : 9780198548928
Total Pages : 473 pages
Book Rating : 4.23/5 ( download)

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Download or read book Host-parasite Evolution written by Dale H. Clayton and published by Oxford University Press, USA. This book was released on 1997-01-01 with total page 473 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a question-oriented volume with a solid organismal foundation that will help to bridge the gap between evolutionary ecologists and parasitologists. A range of experts have written chapters that review general concepts and provide a detailed survey of the parasites of a major group of hosts. The book concludes with extensive reviews of methods used to study bird parasites. It is a novel and valuable tool for anyone interested in understanding host-parasite interactions, particularly from an evolutionary perspective.

Author : Samantha Fowler
Publisher :
ISBN 13 : 9789888407453
Total Pages : 618 pages
Book Rating : 4.57/5 ( download)

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Download or read book Concepts of Biology written by Samantha Fowler and published by . This book was released on 2018-01-07 with total page 618 pages. Available in PDF, EPUB and Kindle. Book excerpt: Concepts of Biology is designed for the single-semester introduction to biology course for non-science majors, which for many students is their only college-level science course. As such, this course represents an important opportunity for students to develop the necessary knowledge, tools, and skills to make informed decisions as they continue with their lives. Rather than being mired down with facts and vocabulary, the typical non-science major student needs information presented in a way that is easy to read and understand. Even more importantly, the content should be meaningful. Students do much better when they understand why biology is relevant to their everyday lives. For these reasons, Concepts of Biology is grounded on an evolutionary basis and includes exciting features that highlight careers in the biological sciences and everyday applications of the concepts at hand.We also strive to show the interconnectedness of topics within this extremely broad discipline. In order to meet the needs of today's instructors and students, we maintain the overall organization and coverage found in most syllabi for this course. A strength of Concepts of Biology is that instructors can customize the book, adapting it to the approach that works best in their classroom. Concepts of Biology also includes an innovative art program that incorporates critical thinking and clicker questions to help students understand--and apply--key concepts.

Author : Helmut König
Publisher : Springer Science & Business Media
ISBN 13 : 9783540281801
Total Pages : 522 pages
Book Rating : 4.00/5 ( download)

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Download or read book Intestinal Microorganisms of Termites and Other Invertebrates written by Helmut König and published by Springer Science & Business Media. This book was released on 2006 with total page 522 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first work to focus on microbes in gut systems of soil animals. Beginning with an overview of the biology of soil invertebrates, the text turns to the gut microbiota of termites, which are important soil processors in tropical and subtropical regions. Coverage extends to intestinal microbiota of such other litter decomposers as earthworms, springtails, millipedes, and woodlice. Thoroughly illustrated, including color photographs.

Author : Beth Okamura
Publisher : Springer
ISBN 13 : 3319147536
Total Pages : 441 pages
Book Rating : 4.36/5 ( download)

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Download or read book Myxozoan Evolution, Ecology and Development written by Beth Okamura and published by Springer. This book was released on 2015-04-01 with total page 441 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an up-to-date review of the biology of myxozoans, which represent a divergent clade of endoparasitic cnidarians. Myxozoans are of fundamental interest in understanding how early diverging metazoans have adopted parasitic lifestyles, and are also of considerable economic and ecological concern as endoparasites of fish. Synthesizing recent research, the chapters explore issues such as myxozoan origins; evolutionary trends and diversification; development and life cycles; interactions with hosts; immunology; disease ecology; the impacts of climate change on disease; risk assessment; emerging diseases; and disease mitigation. This comprehensive work will appeal to a wide readership, from invertebrate zoologists, evolutionary biologists and developmental biologists to ecologists and parasitologists. It will also be of great practical interest to fisheries and conservation biologists. The identification of key areas for future research will appeal to scientists at all levels.

Author : Robert Poulin
Publisher : Princeton University Press
ISBN 13 : 9781400840809
Total Pages : 360 pages
Book Rating : 4.05/5 ( download)

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Download or read book Evolutionary Ecology of Parasites written by Robert Poulin and published by Princeton University Press. This book was released on 2011-06-27 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: Parasites have evolved independently in numerous animal lineages, and they now make up a considerable proportion of the biodiversity of life. Not only do they impact humans and other animals in fundamental ways, but in recent years they have become a powerful model system for the study of ecology and evolution, with practical applications in disease prevention. Here, in a thoroughly revised and updated edition of his influential earlier work, Robert Poulin provides an evolutionary ecologist's view of the biology of parasites. He sets forth a comprehensive synthesis of parasite evolutionary ecology, integrating information across scales from the features of individual parasites to the dynamics of parasite populations and the structuring of parasite communities. Evolutionary Ecology of Parasites presents an evolutionary framework for the study of parasite biology, combining theory with empirical examples for a broader understanding of why parasites are as they are and do what they do. An up-to-date synthesis of the field, the book is an ideal teaching tool for advanced courses on the subject. Pointing toward promising directions and setting a research agenda, it will also be an invaluable reference for researchers who seek to extend our knowledge of parasite ecology and evolution.

Author : Sarah P. Otto
Publisher : Princeton University Press
ISBN 13 : 1400840910
Total Pages : 745 pages
Book Rating : 4.15/5 ( download)

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Download or read book A Biologist's Guide to Mathematical Modeling in Ecology and Evolution written by Sarah P. Otto and published by Princeton University Press. This book was released on 2011-09-19 with total page 745 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thirty years ago, biologists could get by with a rudimentary grasp of mathematics and modeling. Not so today. In seeking to answer fundamental questions about how biological systems function and change over time, the modern biologist is as likely to rely on sophisticated mathematical and computer-based models as traditional fieldwork. In this book, Sarah Otto and Troy Day provide biology students with the tools necessary to both interpret models and to build their own. The book starts at an elementary level of mathematical modeling, assuming that the reader has had high school mathematics and first-year calculus. Otto and Day then gradually build in depth and complexity, from classic models in ecology and evolution to more intricate class-structured and probabilistic models. The authors provide primers with instructive exercises to introduce readers to the more advanced subjects of linear algebra and probability theory. Through examples, they describe how models have been used to understand such topics as the spread of HIV, chaos, the age structure of a country, speciation, and extinction. Ecologists and evolutionary biologists today need enough mathematical training to be able to assess the power and limits of biological models and to develop theories and models themselves. This innovative book will be an indispensable guide to the world of mathematical models for the next generation of biologists. A how-to guide for developing new mathematical models in biology Provides step-by-step recipes for constructing and analyzing models Interesting biological applications Explores classical models in ecology and evolution Questions at the end of every chapter Primers cover important mathematical topics Exercises with answers Appendixes summarize useful rules Labs and advanced material available